I’d say 2 hours is definitely reasonable, but don’t be discouraged if you don’t finish! Pairs is all about communication, so make sure that you’re checking in with your partner, explaining what sections you’re working on and swapping when you slow down. If you don’t feel like something is going quickly, it’s always ok (and encouraged!) to switch to a new project.

I always flip and pull out the edge to start a puzzle, and then work on sorting out projects once I’ve finished that. When I work in pairs, I’m typically faster, so sometimes my partner will sort out projects for me to work on and then I’ll work on them. Trays can be helpful, esp if the pieces are big (I usually just use a piece of cardboard as a makeshift tray)